Last April, Becht Engineering completed a walk-down of a client’s refinery jet fuel treating system from the MEROX unit down through the polishing unit operations, including the salt and clay treating towers. Becht worked closely with the client to continue the investigation around root causes of recent severe operating difficulties meeting the ASTM Jet Fuel Thermal Oxidation Test (JFTOT), and to provide further technical analysis toward ranking considerations in the previously submitted RCFA Report.

What We Did

The Becht team was accompanied by a chief area operator and other supporting process engineers knowledgeable of the jet fuel treating system. Together, multiple 1-liter sample bottles were filled consecutively at various existing sample point locations along the jet fuel treating sequence, including low-point drains between process vessels where no routine sample point exists.

All of the jet fuel treating vessels and interconnecting pipework were externally inspected for piping configurations that include horizontal sections followed by vertical risers that could act as liquid traps for caustic, as Bob had encountered this phenomenon in other jet fuel processing units.

Based on our SME’s experience in evaluating numerous other jet fuel treating systems, it was Becht Engineering’s impression that client’s system was in relatively robust shape, but with some separation units undersized. Several retrofit improvements had been made on the client’s side, and the Becht team concluded that the MEROX Unit section was performing well, but dealing with ongoing contaminant issues destabilizing the JFTOT test which compounded the challenges of undersized separation equipment.

Conclusion

The Becht team concluded that the client’s jet fuel treating system was suffering JFTOT reliability issues due to high levels of surfactants, likely entering the facility with the crude oil, and leading to hazy jet fuel which increases the likelihood that contaminants will lower JFTOT reliability. Several recommendations were submitted to the client including improved sampling and monitoring procedures, new analytical procedures to generate leading indicators of JFTOT quality deterioration, cutting edge technology in filtration and coalescing technology, optimized drying techniques, and finally the SME performed a small-scale tabletop analytical demonstration confirming that the prescribed improvements would greatly lower moisture and haze content.